code: def get_from_facet_mapping(data_name, facet_mapping):
      while data_name in facet_mapping:
          data_name = facet_mapping[data_name]
      return data_name
  
file_path: vegafusion/python/vegafusion/vegafusion/evaluation.py
imports: from altair import data_transformers, Chart, FacetChart, LayerChart, HConcatChart, VConcatChart, ConcatChart
  from altair.utils.schemapi import Undefined
label_desc: Use image node_id 6 for calling a global function with example usage: get_from_facet_mapping(data_name, facet_mapping) and returns: data_name